RMS to Watts Calculator

Find power from RMS voltage and resistance.

Power (W) 1,440

Formula: W = V² ÷ R

Step-by-step with your numbers:

1. Values used:

2. Voltage (RMS) = 120 V

3. Resistance = 10 Ω

5. Power = 1,440W

Did we solve your problem today?

For a resistive load (like a heater), AC power is the same formula as DC.

The math behind it

W = V_RMS² ÷ R. The RMS voltage gives the same heating power as DC.

120 V, 10 Ω → 1,440 W.

AC or DC?

Both — RMS voltage is the equivalent DC value for power.